- Gain expert knowledge of the physical layer of the OSI model (Chapter 3)- Learn about different wireless technologies, including infrared and radio (Chapter 4)- Use the circuit and packet switched transmission facilities (Chapters 16-17)- Discover how to use modems and dial-up technologies in your WAN (Chapter 17)- Manage and fine-tune your network's performance (Chapter 20)- Secure the data on your network (Chapter 21)- Build fault-tolerant systems using redundant arrays of inexpensive disks-RAID (Chapter 22)- Learn about the different types of remote access for NT networks (Chapter 23)- Prevent and troubleshoot problems with your network (Chapters 25-26)- Discover how intranets, extranets, and VPNs differ, and when their deployment makes sense (Chapter 25).